题目

A few months ago the potato was considered an enemy in the obesity battle but a new study shows the food isn't that bad after all． In June，researchers from Harvard University found that eating some of the potato[]every day，whether mashed（被磨碎），deep fried or baked，caused more weight gain than an extra can of drink or red or some kind of meat．The conclusion was that it happened because potatoes were always cooked﹣﹣﹣﹣﹣making it easier for the body to change the starch（淀粉） which would increase the blood sugar levels．The body then had to work extra har卢瑟福α粒子散射实验的结果表明（　　）A．可以用人工方法研究原子核的结构B．原子有全部正电荷集中在原子中央很小的体积内C．质子比电子轻D．原子核内存在中子